Container closure construction



May 5, 1942. c. T. DRAPER I CONTAINER CLOSURE CONSTRUCTION Filed Dec. 16, 1958 W w 6 w 2 llllllllllll,Illllllllllllllllllllllll 3 e n MM m 0 m 0 May 5, 1942 CONTAINER CLOSURE CONSTRUCTION Charles T. Draper, Cleveland Heights, Ohio, as-

signor to The Draper Manufacturing Company, Cleveland, Ohio, a corporation of Ohio Application December 16, 1938, Serial No. 246,118

2 Claims.

The invention relates generally to bung openings for metallic containers, barrels, drums, vessels, packages and the like utilized for shipping, storing and dispensing fluid, liquid or semi-solid materials; and relates more particularly to an improved and simplified closure construction consisting of a threaded sheet metal bung opening neck or ring integral with a container wall and a threaded sheet metal plug therefor.

Metallic containers are extensivelyv used for transporting, storing and dispensing various kinds of lubricating oils and the like, and such containers are usually provided with means for preventing undetectable tampering with the closure structure.

Metallic containers heretofore have been provided almost universally with cast, forged or specially pressed bung rings or bushings having internal threads; and threaded plugs have heretofore ordinarily been made of cast iron. drop forgings or pressed steel stampings.

In accordance with the prior practice, the bung rings have been secured in a liquid-tight manner to thecontainer wall by seaming, welding or the like; and threads have been provided in the bung ring and plug by cutting the same in the annular walls thereof in accordance with usual methods.

The manufacture of such bung rings and plugs, the threading of the same, and the securing of the bung rings to the container wall, are each relatively expensive operations, adding materially to the cost of manufacturing metallic containers,

in addition to the increased cost incident to the use of special metals in certain instances.

Thus the composite expense involved, due to the amount or character of metal used and the threading thereof, in the manufacture of threaded bung openings and plugs constituting a container closure construction in accordance with prior practice, is relatively large with respect to the total cost of manufacturing a sheet metal container; and such prior closure constructions frequently require two-or more gaskets in order to render the closure construction liquid-tight.

It is therefore a primary object of the present invention to appreciably reduce the cost of menuiacturing metallic containers, by greatly reducing the disproportionate cost of providing the bung opening and closure construction therefor, without, however, sacrificing complete container drainage, a liquid-tight construction. or adaptability for the reception of tamper sealing means.

The threads in a threaded bung opening of a metallic container are usually formed as standard pipe threads because the bung openings must be adapted for the reception of standard pipe threaded fittings; and the closure plugs therefor must necessarily be provided'with standard pipe roads which have a particular shape for any particular size of opening and which also have a V-sided or V- shaped thread form with the angle of the V being degrees.

Metallic containers are usually made from sheet, strip or plate metal of from 24 to as heavy as 12 gauge material; but ordinarily the thickness of the metal in the plug need not begreater than that in the container wall if the plug is made of sheet metal, except for the prior practice requirement of much thicker plug metal in order to allow for cutting the pipe threads therein.

I have developed an entirely new type of integral threaded bung opening for a metallic container by providing a sheet metal wall of a container with an integral tubular neck having internal and external V-sided threads formed therein, one of which is a standard pipe thread, and the metal forming the. internal and external pipe threads being internally and externally swaged throughout as shown in my Patent No. 2,156,237.

The threading of such a neck may be carried out on apparatus such as disclosed in my Patent No. 2,145,587; and such a structure may be made, and provided with a flange at the outer end of the neck if desired, in accordance with the method disclosed in'my copending application Serial No. 246,119, filed of even date herewith.

I have also developed an entirely new type of ing application Serial No. 207,285, filed May 11,

1938; and the present closure construction canstitutes improvements upon the closure construe tions shown in said Patent No.'2,156,237, said application Serial No. 207,285, and in the division thereof application Serial No. 269,545.

I have discovered that if a sheet metal container is provided with a bung opening neck or ring formed from thin gauge rolled steel as distinguished from tin plate, or cast or forged or heavy plate metal, and if a sheet metal plug is also provided made from thin gauge rolled steel, and if the sheet metal plug and ring are each provided with internal and external threads by swaging, deforming, cold rolling, ironing, burnishing, spinning, smoothing and hardening the metal in an annular wall thereof by working the same between roller dies to provide a standard V-sided internal pipe thread in the bung ring and a standard V-sided external pipe thread in the plug, no seizing of metal to metal occurs when such a plug is threaded into such a bung ring, which seizing ordinarily occurs when two threaded steel members are engaged.

It is therefore an object of the present invention to provide a closure construction for a metallic container including a sheet metal bung ring and a sheet metal plug each having a threaded annular wall, the metal of which is swaged, deformed, cold rolled, ironed, burnished, spun, smoothed and hardened to form pipe threaded surfaces which may be engaged without seizing.

It is a further object of the present invention to provide a metallic container with a sheet metal bung ring and plug closure construction in which the sheet metal bung ring and sheet metal plug are formed at their outer ends each with an outturned flange, one of which flanges is provided with a shoulder, for clamping a liquid sealing gasket between the flanges upon threading the plu into the bung ring.

Moreover, it is an object of the present invention to provide a metallic container with a sheet metal bung ring and plug closure construction in which the sheet metal bung ring and sheet metal plug are formed at their outer ends each with an outturned flange, and in which the plug flange terminates in a downturned annular .flange formed so as to overlap and protect not only the bung ring flange, but also the liquid sealing gasket clamped between the plug and bung ring flanges, when the plug is threaded into the bung ring.

Moreover, it is an object of the present invention to provide a metallic container with a threaded flanged sheet metal bung ring and plug closure construction in which tamper sealing means is secured to or around the plug and bung ring flanges for preventing undetectable access to the contents of the container.

And finally, it is an object of the present invention to provide a metallic container with a threaded sheet metal bung opening and plug closure construction which accomplish the aforesaid desiderata, which greatly simplifies present day bung opening constructions for metallic containers, which may be manufactured at a much lower cost than closure constructions now in use, and which provides a most efficient closure for a metallic container.

These and other objects may be obtained by the elements, parts, combinations and constructicns constituting the present invention, preferred embodiments of which are shown in the accompanying drawing and are hereinafter claimed and described in detail, which may be stated in general terms as including in metallic container closure construction a wall provided with a preferably integral tubular sheet metal neck forming a bung opening for the container projecting or extending preferably outwardly of the container from the wall, the neck terminating in an outturned annular flange preferably extended outward by a flanged ring to form a shoulder on the bung opening flange, the neck between the wall and flange being deformed and swaged to provide an internal standard V-sided pipe thread formation therein; a closure plug including a sheet metal closing wall provided with an integral tubular neck, the neck terminating in an outturned annular flange lapping the extended shouldered bung ring flange, the plug neck between thefclosure wall and flange being deformed and swaged to provide an exter-- nal standard V-sided pipe thread formation therein for threaded engagement with the threadterminating in a downturned annular flange surrounding the extended shouldered bung ring flange; preferably a single gasket clamped between the outturned plug and bung ring flanges and protected by the downturned plug flange; and tamper sealing means engaged with or around the plug and bung ring flanges.

In the accompanying drawing,

Figure 1 is a plan view of the improved closure construction with certain parts broken away;

Fig. 2 is a vertical section taken on the line 2-2,Fig. 1;

Fig. 3 is a vertical section taken on the line 3-3, Fig. 1;

Fig. 4 is an enlarged view of a portion of Fig. 3; and

Fig. 5 is a view similar to Fig. 2, showing a modified form of tamper proof seal.

Similar numerals refer' to similar parts throughout the various flgures of the drawing.

A sheet metal container wall is indicated at I] in the drawing and i provided with an integral threaded bung opening wall ll having a flange l2 at its outer end; and the threaded wall or neck II is preferably surrounded by a. ring ll having a flange I4, which engages the neck flange from beneath and extends outwardly therefrom and forms with the flange l2 a shoulder I5. Such a hung opening construction is the same as that set forth in my Patent No. 2,156,237 and said applications Serial Nos. 207,285 and 269,545.

The flange l4 may be and preferably is provided with an annular step ii adjacent to the outer edge of flange I! so as to reduce the depth of the shoulder l5; and ring I3 is preferably clamped to threaded neck II and container wall I0 between flange I2 and wall l0. Neck H may be threaded in apparatus such as disclosed in my Patent No. 2,145,587, and may be made in accordance with the method set forth in my copending application filed of even date herewith, Serial No. 246,i.l9.

An improved threaded sheet metal closure plug is generally indicated at l1 having a closing wall 18, which terminates in an integral threaded annular or tubular wall is; and wall [9 terminates ed bung ring neck, the outturned plug flange in an integral .outturned flange 20 which is formed at its outer edge with a downturned annular flange 2 I.

The plug I! is provided with wrench engaging means, as by spot welding at 22 the ears 23 of a sheet metal U bar 24, which may be internally reinforced by bar 25. Thus, the member 24 may be engaged by a wrench or other tool for screwing or unscrewing the plug ll into or out of the threaded bung opening.

The improved plug I! may be made from a cup-shaped blank and threaded in the manner disclosed in my copending application Serial No. 207,285.

In making the threaded portions II and I! as stated, the annular sheet metal walls are swaged, deformed, cold rolled, ironed, burnished, spun, smoothed, hardened and worked between roller dies to provide the internal and external V-sided pipe threads therein, one of which is a standard pipe thread. This working operation thickens the threaded walls in various regions so that the thickness of the swaged metal in thethread apices is greater in a diametrical direction than the thickness of the swaged metal in the side wall of 'a thread common to both the internal and external thread surfaces.

In carrying out the thread forming operation,

sufficient pressure is applied and maintained between the roller dies and the cold rolling and ironing is carried out for a sufficient number of revolutions that accurate V-shaped pipe threads are formed. As a result, the thread formations present very smooth, cold rolled surfaces which will not seize, even though plug l1 and threaded neck II are both steel.

When the plug I1 is threaded into the threaded neck II, a liquid sealing gasket 26 which may be fiber, rubber or other suitable material, is interposed between flange 20 and flanges l2 and I4 so that the gasket 26 is compressed between the same and particularly against the shoulder IE to form a liquid-tight joint between the plug and bung ring integral with wall In. Thus, only a single gasket is required or used to form a liquid-tight closure for the bung opening.

If desired, a tamper-proof sealing cap 21 may be placed over the plug l1 and have its downwardly extending rim 28 turned inward at 29 (Figs. 1, 2, 3 and 4) by a suitable tool to engage under the flange I4 adjacent to the step H; for sealing the closure against unauthorized opening.

Alternately, as shown in Fig. 5, U bar 24 may be perforated at 30 and a clip 3| may be spot welded to the container wall In and formed with an aperture 32 whereby a lead and wire seal 33.

may be secured through apertures 3|] and 32 to seal the closure against unauthorized opening.

Thus, tamper seal 21 is not only engaged with, but is engaged around the flanges on the plug and hung ring; and tamper seal 33 is engaged around the plug and bung ring flanges and is engaged wth parts integrally connected to the plug and bung ring flanges.

Downturned flange 2| on plug I! has severa functions. First, flange 2| provides a smooth outer surface for the outer edge of the plug and bung ring when the plug is threaded into the bung ring. Second, flange 2| in lapping the outer edge of flange l2 extended by flange l4, closes off the edge of the bung ring flange to prevent injury or damage thereto. Third, flange 2| closes off the space between plug flange 20 and bung ring flange l2 extended by flange l4 so as to protect gasket 26 from injury or damage and provide a further wall against which gasket 26 abuts when it is compressed between flange 20 and flange l2 extended by flange l4.

Accordingly, the present improvements appreciably reduce the cost of metallic container construction and of the closure construction therefor; provides a sheet metal bung'ring and closure plug formed with standard pipe threads without cutting the threads; provides threaded steel parts, which when engaged will not seize; provides a structure having a very efficient liquidtight seal formed with a single gasket, which is protected; and provides a closure construction which may be readily sealed in any one of several ways in a tamper-proof manner. y

In the foregoing description, certain terms have been utilized for brevity, clearness and understanding; but no unnecessary limitations are to implied therefrom beyond the requirements of the prior art; because such words are utilized for descriptive purposes herein and not for the purpose of limitation, and are intended to be broadly construed.

Moreover, the invention is not limited to the exact structure shown herein because the size of the various parts may be varied to provide other structural embodiments without departing from the scope of the present invention.

The words sheet metal" used herein and in the claims are intended to include sheet, strip or plate metal of the desired or necessary gauge, including steel, or other metals from which it may be desired to construct metallic containers; the words "standard pipe threads are intended to refer to the various standard pipe threads which are standard in various countries of the world, all of which threads have V sides; and the words shouldered flange are intended to include a flange on the end of either the bung ring or plug formed with a shoulder whether said flange is made of one or two pieces, as long as the same is formed from sheet metal.

Certain subject matter disclosed but not claimed herein is claimed in my copending applications Serial Nos. 207,285 and 269,545.

Having now described the features of the invention, the construction, manufacture and use of a preferred form of the same, and the advantages and results obtained by the improved construction; the new and useful parts, elements, combinations, constructions and devices, and reasonable mechanical equivalents thereof obvious to those skilled in the art, are set forth in the appended claims.

I claim:

1. In metallic container closure construction, a sheet metalwall provided with an integral standard pipe threaded tubular neck forming a bung opening, the neck terminating in an outturned flange, a ring surrounding said neck and having an outturned flange engaging the neck flange from beneath and extending outwardly there- .from and-forming therewith a shoulder, a sheet metal closure plug having a standard pipe threaded tubular portion threaded into said neck and having a flange lapping said shouldered flange, the threaded sheet metal tubular portions of said neck and plug being internally and externally roller, swaged throughout, a downturned annular flange at the outer edge of said plug flange surrounding said extended shouldered neck flange, a single gasket clamped between the outturned plug flange and shouldered flange andenclosed by said downturned flange providing a liquidtight seal for said opening, and tamper sealing means engaged around said flanges.

2. In metallic container closure construction, a sheet metal wall provided with an integral standard pipe threaded tubular neck forming a bung opening, the neck terminating in an outturned flange, a ring surrounding said neck and having an outturned flange engaging the neck flange from beneath and extending outwardly therefrom and forming therewith a shoulder, a sheet metal closure plug having a standard pipe threaded tubular portion threaded into said neck and having a flange lapping said shouldered flange, the threaded sheet metal tubular portions of said neck and plug beinginternally and externally roller swaged throughout, a downturned annular flange at the outer edge of said plug flange, a single gasket clamped between the out-- turned plug flange and shouldered flange and enclosed by said downturned flange providing a liquid tight seal for said opening, and tamper sealing means engaged around said flanges.

CHARLES T. DRAPER. 

